Bird Trip: Me Sunday April 29 or May 6? Need binoculars? Transportation?

Outline Community Ecology –Indirect effects, Keystone species, Invasive species –Biodiversity: importance and evaluation –The new paradigm in ecology: communities in flux –Conservation of species interactions Ecosystem Ecology –Ecosystem services –Biodiversity and ecosystem services –Ecosystems of special concern (Marine and Tropical)

Purple Loosestrife Benefits of Biological Control –Mediate spread –Restore interactions –Conserve endangered species Risks of Biological Control –Unintended ecological consequences

How Risky is Biological Control? 800 spp. of snails have evolved in Hawaii islands. Rosy Wolf-Snail introduced to control Giant African Snail % of native land snails extinct. Simberloff, D., and P. Stiling How risky is biological control? Ecology 77:

Gypsy Moths: Entomophaga maimaiga

Island Communities Some of the “best” examples of invasive species come from island communities –Brown tree snake on Guam –Rosy wolf-snail in Hawaii Possible reasons –Low Diversity (1° factor: discuss later) –Relaxed selection (2° consequence of low diversity)

Biodiversity (1) (2) (3)

Biodiversity Richness Shannon-Wiener Simpson’s Endemicity *In nature, different “diversity indices” typically give similar results

Biodiversity Richness: Total number of spp. Evenness: The distribution of individuals among spp.

How do we determine species richness? BIOBLITZ: Total species found in 695 acres over 24 hours - 1,369

Measuring Biodiversity: Extrapolation ~ 1200 beetle spp. in canopy of Luehea seemanii. ~ 13.5 % (163 spp.) of beetles are specialists. ~ 50,000 tropical tree spp. Beetles ~ 40% of insect diversity. ~ 2/3 insects found in canopy, 1/3 on ground ~30 million insect spp.

Measuring Biodiversity: Estimators For more info, see: Colwell, R. K., and J. A. Coddington Estimating terrestrial biodiversity through extrapolation. Phil.Trans.R.Soc.Lond.B. 345: Samples Species NOTE: Species richness increase with sampling effort Goal: sample here, extrapolate there

ALAS “How many arthropod species are there in a tropical rainforest?... Systematists use a "find them all" approach... Community ecologists, in contrast, use a "sample and estimate" approach. Project ALAS combines both traditions in an assessment of arthropod diversity. "Sample and estimate" methods are used to sample a set of broad "survey taxa," while "find them all" methods are used to sample much more thoroughly a set of smaller "focal taxa." The known focal taxa are then used to calibrate and evaluate and compare the sampling and estimation methods.”

Is Biodiversity Important? Conservation Biology Perspective –Inherently valuable Utilitarian Perspective –Natural resources: Genetic libraries; natural design Ecological Role –Invasibility –Stability –Ecosystem Function